Doc system for AI to understand multiple repos

So I am working on a modular system, and I have template starters that clone and have their own git repo, but pull from upstream.

The problem I am having is how to communicate to AI (I use Claude code - web browser version) how all the modules fit together seamlessly. When at the moment they currently only have their own docs folder, and aligned with their upstream templates.

Any ideas on how best to automate the docs to be system wide, rather module only. I'd like AI to write the docs, and rules so they aren't making it up as they go when we generate modules.

Have only touched on Astro, have a docs repo (and using sub repo - but struggling with AI being able to push to it).

And discussing with AI, brainstorming tends to over complicate things. Maybe someone has an out of the box idea or option they've used?